Hydration is an important component of elite performance, but it is also important in every-day life.
Gold Coast Suns Performance Dietitian and Chef Ben Parker discusses how dehydration occurs, how it affects performance and the easy steps you can take to ensure a healthy lifestyle.
How your body gets dehydrated
“You sweat to cool your body down, it’s the evaporation of sweat that cools the body, obviously you are losing water,” he says.
“The amount of water loss depends on how hot it is, how hard you are working and your sweat rate.
“Water has to come from somewhere, it comes from your blood. As you lose water, your blood loses volume, your body can tolerate that to a certain point and your kidneys will regulate that blood volume.
“Studies show that once you get to two to three percent of your bodyweight loss due to dehydration, it starts to effect performance.
How it affects performance
Parker says that dehydration can have a significantly negative impact on performance. It is why the Suns coaching staff and players monitor their hydration levels very closely.
“Your blood volume is being decreased. Your body kicks into its survival mechanism.
“The physical exertion from exercise is causing metabolic heat, the heat is causing you to sweat. At some point the body will reduce the amount of physical exertion you can do to stop the heat generation.
“As your water loss increases, the body puts the breaks on how much energy you can expend and thus physical performance decreases.
“It affects cardiac output causing fatigue and can have cognitive effects on things such as decision making, reaction time, mood and memory.”
“Our players weigh themselves before and after training, so they are monitoring their weight loss and dehydration in sessions. We Also monitor USG (urinary specific gravity) for key sessions and games,” he says.
“A kilogram of weight lost is a kilogram of water lost. You want to try to drink back 150% of your losses. That gives the players a target of how much they need to drink during training or during a game and in the recovery phase.
“The players basically can’t drink enough during preseason in the Gold Coast Summer, or when we play in hot environments such as Darwin, but for general population, you don’t want to be drinking so much water that you are gaining weight.
The role of Electrolytes
“Electrolytes are; sodium, potassium, magnesium and calcium. They are in the blood.
“Sodium is the main electrolyte. The role of sodium is that it causes osmosis – moving water to your sweat gland and from the sweat gland to the surface of your skin.
“As you are sweating, you are losing some salt, the sodium draws the salt into the sweat gland where the sweat gland itself conserves sodium, so the water comes out of the skin.
“Although you do loose some sodium, you lose more water than sodium, as you sweat and your blood sodium concentration actually goes up, because there is less water.
“If you take electrolytes, you are adding in more sodium, so you’re pouring more sodium on top of an already increased blood sodium level. That’s the reason you don’t need to drink electrolytes during training in most circumstances.
“We use Gatorade for the carbohydrates. It has electrolytes, but it is really good for adding carbohydrates which help with fuelling intense training sessions and recovery.”
Three easy steps
There are three easy things you need to monitor to keep on top of hydration.
“There are three markers of hydration; thirst, urine colour and body weight loss,” Parker says.
“If you can monitor those three, you can tell whether you are dehydrated. They are very accurate markers to know if you are dehydrated.
“The thirst sensation is your body telling you that you are dehydrated.
“Generally, the hours proceeding exercise the thirst will map on to your dehydration, you’ll feel thirsty and drink more. It’s pretty accurate, it’s worked for millennia.”
